Landowner Perceptions Of The Value Of Natural Forest And Natural Grassland In A Mosaic Ecosystem In Southern Brazil

The forest-grassland mosaics of southern Brazil have been subject to many land use and policy changes over the decades. Like many grasslands around the world, the Campos grasslands are declining with few conservation efforts underway. In contrast, forests receive much attention and many incentives. It is hypothesized that perception of land cover has the potential to shape ecosystems. Here we conduct a questionnaire to further our understanding of decision-making practices that alter landscapes (Campos grassland, Araucaria forest, agriculture and plantation) and direct land policies in the region. Our analysis reveals that plantations are significantly less desirable than the other landscape types. However, plantation land use has increased by 87 % over the past few decades, as a result of industry and government incentives. The proportions of other landscape types have remained consistent over the past two decades. Restoration of native vegetation is not a priority of landowners and restoration would require a financial incentive.Natural Sciences and Engineering Research Council of CanadaJames S. McDonnell Complex Systems Scholar Awar

Towards an applied metaecology

The complexity of ecological systems is a major challenge for practitioners and decision-makers who work to avoid, mitigate and manage environmental change. Here, we illustrate how metaecology - the study of spatial interdependencies among ecological systems through fluxes of organisms, energy, and matter - can enhance understanding and improve managing environmental change at multiple spatial scales. We present several case studies illustrating how the framework has leveraged decision-making in conservation, restoration and risk management. Nevertheless, an explicit incorporation of metaecology is still uncommon in the applied ecology literature, and in action guidelines addressing environmental change. This is unfortunate because the many facets of environmental change can be framed as modifying spatial context, connectedness and dominant regulating processes - the defining features of metaecological systems. Narrowing the gap between theory and practice will require incorporating system-specific realism in otherwise predominantly conceptual studies, as well as deliberately studying scenarios of environmental change. (C) 2019 Associacao Brasileira de Ciencia Ecologica e Conservacao. Published by Elsevier Editora Ltda.Peer reviewe

Understanding forest-grassland mosaics: three case studies on the basaltic plateaus in humid subtropical Brazil

Los paisajes que muestran mosaicos de ecosistemas naturales contrastantes, como bosques y pastizales, frecuentemente resultan de difícil interpretación en cuanto a los factores operativos detrás de dichos mosaicos. Nuestro trabajo en los altiplanos efusivos de Rio Grande do Sul, Brasil, muestra que los factores responsables de los mosaicos de cobertura-uso de la tierra a escala regional, pueden identificarse analizando los patrones de vegetación y su relación con procesos geomorfológicos y pedológicos que controlan la oferta de agua y de nutrientes, a los que se superponen procesos ligados al uso de la tierra. El análisis se llevó a cabo en dos escalas espaciales, la regional que abarcó una porción significativa de los altiplanos, y la local (del paisaje) en tres sitios contrastantes por sus características físicas y de uso. Los pastizales naturales o campos aún cubren buena parte de las mesetas más altas sobre suelos jóvenes (inceptisoles) pero muy empobrecidos en nutrientes, en tanto que en las mesetas a menor altitud, los campos (sobre oxisoles profundos), han sido extensivamente remplazados por cultivos anuales. Los bosques montanos dominados por Araucaria angustifolia se encuentran en las mesetas altas, restringidos mayormente a sitios con provisión de agua todo el año y fuera del alcance de los incendios del pastizal. El bosque semidecíduo se limita a las mesetas bajas donde ocupa las posiciones topográficas más bajas. En todos los casos el uso actual, agrícola o forestal, dificulta la interpretación, pero la estrecha correspondencia entre sitios con mayor disponibilidad de nutrientes y bosques sugiere que el factor nutricional desempeña un rol esencial en los actuales patrones de vegetación. A su vez la disponibilidad de nutrientes o fertilidad potencial está condicionada por la erosión de la peniplanicie y el rejuvenecimiento del paisaje producido por la erosión regresiva de los cursos de agua. Presentamos finalmente un modelo conceptual de la distribución de los ecosistemas naturales y del uso de la tierra, donde se interrelacionan todos estos procesos operativos a distintas escalas espaciales y temporales.110-128marcela.pinillos@yahoo.com.arsemestralLandscapes exhibiting complex mosaics of contrasting natural ecosystems, like forests and grasslands, continue to evade a straightforward interpretation concerning the key drivers behind the landscape mosaic. Our research shows that the high-level drivers of the land cover - land use mosaics, characteristic of the basaltic tablelands of northern Rio Grande do Sul, Brazil, can be identified based on analysis of the vegetation pattern in relation to geomorphic and pedogenetic phenomena controlling water and nutrient supply, together with human action. The analysis is implemented on two spatial scales: one regional, embracing a large portion of tablelands, and the other at the landscape scale by selecting three contrasting sites. Natural grasslands (campos) still extend over much of the highest plateaus, on young but nutrient-depleted inceptisols. While on the lower altitudes campos over deep oxisols have been extensively replaced by cash crops. The Araucaria angustifolia montane forest characterizes the higher tablelands, where it occurs in habitats with a permanent water supply and out of the reach of the frequent grasslands fires. Semideciduous forests occur on the lower plateaus, restricted to the wet conditions of the bottomlands. In any case, the increasingly widespread human disturbance renders the natural pattern fuzzy, but the close correspondence between more fertile habitats and forest occurrence suggests that nutrient availability plays a key role. Nutrient availability, in turn, results from enhanced rates of erosion wearing out the ancient peniplain and further developing the drainage system. A conceptual model relating geomorphic, pedogenetic and human factors is proposed to explain the original and actual vegetation mosaics

Long-term ecological research in southern Brazil grasslands: Effects of grazing exclusion and deferred grazing on plant and arthropod communities

Grazing exclusion may lead to biodiversity loss and homogenization of naturally heterogeneous and species-rich grassland ecosystems, and these effects may cascade to higher trophic levels and ecosystem properties. Although grazing exclusion has been studied elsewhere, the consequences of alleviating the disturbance regime in grassland ecosystems remain unclear. In this paper, we present results of the first five years of an experiment in native grasslands of southern Brazil. Using a randomized block experimental design, we examined the effects of three grazing treatments on plant and arthropod communities: (i) deferred grazing (i.e., intermittent grazing), (ii) grazing exclusion and (iii) a control under traditional continuous grazing, which were applied to 70 x 70 m experimental plots, in six regionally distributed blocks. We evaluated plant community responses regarding taxonomic and functional diversity (life-forms) in separate spatial components: alpha (1 x 1 m subplots), beta, and gamma (70 x 70 m plots), as well as the cascading effects on arthropod high-taxa. By estimating effect sizes (treatments vs. control) by bootstrap resampling, both deferred grazing and grazing exclusion mostly increased vegetation height, plant biomass and standing dead biomass. The effect of grazing exclusion on plant taxonomic diversity was negative. Conversely, deferred grazing increased plant taxonomic diversity, but both treatments reduced plant functional diversity. Reduced grazing pressure in both treatments promoted the break of dominance by prostrate species, followed by fast homogenization of vegetation structure towards dominance of ligneous and erect species. These changes in the plant community led to increases in high-taxa richness and abundance of vegetationdwelling arthropod groups under both treatments, but had no detectable effects on epigeic arthropods. Our results indicate that decision-making regarding the conservation of southern Brazil grasslands should include both intensive and alleviated levels of grazing management, but not complete grazing exclusion, to maximize conservation results when considering plant and arthropod communities

Dissecting phylogenetic fuzzy weighting: theory and application in metacommunity phylogenetics

CNPQ - CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICOFAPESP - FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULOFAPERGS - FUNDAÇÃO DE AMPARO A PESQUISA DO ESTADO DO RIO GRANDE DO SULMetacommunity phylogenetics aims at evaluating environmental and/or historical factors driving clade distribution. Phylogenetic fuzzy weighting (PFW) describes clade distribution across metacommunities based on fuzzy sets defined by phylogenetic relatedness among species. The method enables analysing environmental and/or biogeographic determinants of clade distribution. PFW also offers an exploratory tool for visualizing clade distribution via Principal Coordinates of Phylogenetic Structure (PCPS). In this article, we describe the theoretical properties and biological backgrounds of PFW and evaluate its statistical performance (type I error and statistical power) in assessing environmental and phylogenetic determinants of species distribution in comparison with other phylobetadiversity methods (COMDIST, COMDISTNT, Rao's H and UniFrac). The statistical performance of PFW and the other phylobetadiversity metrics was tested by (i) simulating metacommunities under different species assembly scenarios (species distribution influenced or not by environment and/or phylogeny), niche breadth tolerance and species pool sizes; (ii) submitting community matrices to PFW and deriving pairwise phylogenetic dissimilarities between communities (D-P) and PCPS; (iii) submitting these metrics and the other phylobetadiversity methods to different analytical approaches (Mantel test, regression on dissimilarity matrices - ADONIS, and GLM) to evaluate the influence of environment and phylogeny on metacommunity phylogenetic structure; and (iv) estimating type I error and power estimates via alternative permutation procedures. Results demonstrated that PFW provides robust assessment of environmental and phylogenetic drivers of species distribution across metacommunities. Although all methods had acceptable type I error for both Mantel test and ADONIS, only PFW showed acceptable power for both tests. Rao's H had acceptable power only for Mantel test, while COMDIST had acceptable power only for ADONIS. COMDISTNT and UniFrac showed poor statistical performance for both tests. Conversely, GLM had acceptable power only for the first PCPS. Performing ADONIS on D-P provides a robust overall assessment of environmental and phylogenetic drivers of species distribution. On the other hand, performing PCPS analysis after rejecting the null hypotheses via ADONIS allows identifying the phylogenetic nodes mostly associated with environmental gradients. PFW enables synthesizing and analysing phylogenetic patterns in metacommunities, allowing attaining a more complete portrait of ecological and evolutionary drivers of species distribution.Metacommunity phylogenetics aims at evaluating environmental and/or historical factors driving clade distribution. Phylogenetic fuzzy weighting (PFW) describes clade distribution across metacommunities based on fuzzy sets defined by phylogenetic relatedness among species. The method enables analysing environmental and/or biogeographic determinants of clade distribution. PFW also offers an exploratory tool for visualizing clade distribution via Principal Coordinates of Phylogenetic Structure (PCPS). In this article, we describe the theoretical properties and biological backgrounds of PFW and evaluate its statistical performance (type I error and statistical power) in assessing environmental and phylogenetic determinants of species distribution in comparison with other phylobetadiversity methods (COMDIST, COMDISTNT, Rao's H and UniFrac). The statistical performance of PFW and the other phylobetadiversity metrics was tested by (i) simulating metacommunities under different species assembly scenarios (species distribution influenced or not by environment and/or phylogeny), niche breadth tolerance and species pool sizes; (ii) submitting community matrices to PFW and deriving pairwise phylogenetic dissimilarities between communities (D-P) and PCPS; (iii) submitting these metrics and the other phylobetadiversity methods to different analytical approaches (Mantel test, regression on dissimilarity matrices - ADONIS, and GLM) to evaluate the influence of environment and phylogeny on metacommunity phylogenetic structure; and (iv) estimating type I error and power estimates via alternative permutation procedures. Results demonstrated that PFW provides robust assessment of environmental and phylogenetic drivers of species distribution across metacommunities. Although all methods had acceptable type I error for both Mantel test and ADONIS, only PFW showed acceptable power for both tests. Rao's H had acceptable power only for Mantel test, while COMDIST had acceptable power only for ADONIS. COMDISTNT and UniFrac showed poor statistical performance for both tests. Conversely, GLM had acceptable power only for the first PCPS. Performing ADONIS on D-P provides a robust overall assessment of environmental and phylogenetic drivers of species distribution. On the other hand, performing PCPS analysis after rejecting the null hypotheses via ADONIS allows identifying the phylogenetic nodes mostly associated with environmental gradients. PFW enables synthesizing and analysing phylogenetic patterns in metacommunities, allowing attaining a more complete portrait of ecological and evolutionary drivers of species distribution.78937946CNPQ - CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICOFAPESP - FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULOFAPERGS - FUNDAÇÃO DE AMPARO A PESQUISA DO ESTADO DO RIO GRANDE DO SULCNPQ - CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICOFAPESP - FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULOFAPERGS - FUNDAÇÃO DE AMPARO A PESQUISA DO ESTADO DO RIO GRANDE DO SUL303534/2012-5; 302585/2011-7; 307689/2014-0; 563271/2010-8; 457531/2012-62011/50225-32011/2185-

Does disturbance affect bud bank size and belowground structures diversity in Brazilian subtropical grasslands?

Brazilian Campos grasslands are ecosystems under high frequency of disturbance by grazing and fires. Absence of such disturbances may lead to shrub encroachment and loss of plant diversity. Vegetation regeneration after disturbance in these grasslands occurs mostly by resprouting from belowground structures. We analyzed the importance of bud bank and belowground bud bearing organs in Campos grasslands. We hypothesize that the longer the intervals between disturbances are, the smaller the size of the bud bank is. Additionally, diversity and frequency of belowground organs should also decrease in areas without disturbance for many years. We sampled 20 soil cores from areas under different types of disturbance: grazed, exclusion from disturbance for two, six, 15 and 30 years. Belowground biomass was sorted for different growth forms and types of bud bearing organs. We found a decrease in bud bank size with longer disturbance intervals. Forbs showed the most drastic decrease in bud bank size in the absence of disturbance, which indicates that they are very sensitive to changes in disturbance regimes. Xylopodia (woody gemmiferous belowground organs with hypocotyl-root origin) were typical for areas under influence of recurrent fires. The diversity of belowground bud bearing structures decreased in the absence of disturbance. Longer intervals between disturbance events, resulting in decrease of bud bank size and heterogeneity of belowground organs may lead to the decline and even disappearance of species that relay on resprouting from the bud bank upon disturbance. (C) 2014 Elsevier GmbH. All rights reserved

Feedbacks between vegetation and disturbance processes promote long-term persistence of forest-grassland mosaics in south Brazil

Vegetation changes, such as shrub encroachment and forest expansion over grasslands, prairies and savannas have been related to changes in climatic (mainly rainfall and temperature) and atmospheric conditions (CO2 concentration). However, a longstanding question in ecology is how mosaics of forests and open-canopy ecosystems could persist over millennia in sites where climatic conditions favor forests. Here we tested the influence of interactions between grass-tree competition, environmental heterogeneity (topography), seed dispersal, initial density and spatial aggregation of vegetation patches and disturbance behavior (fire) on the long-term coexistence of forests and grasslands in South Brazil. For this, we incorporated the adaptive dynamic global vegetation model (aDGVM) into a spatially explicit modeling approach (2D-aDGVM). Our results showed that recurrent disturbance related to grasses such as fires plays a key role in maintaining the long-term coexistence of forests and grasslands, mainly through feedbacks between disturbance frequency and grass biomass. Topographic heterogeneity affected the rate of forest expansion by adding spatio-temporal variability in vegetation-fire feedbacks. However, the spatial pattern and connectivity of fire-prone (grasslands) and fire-sensitive (forest) vegetation patches were more important to maintain the long-term coexistence of both alternative vegetation states than the initial proportion of forest and grasslands patches. The model is the first individual-based DGVM to consider the combined effects of topography, seed dispersal and fire spread behavior in a spatially explicit approach. (C) 2014 Elsevier B.V. All rights reserved.Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES

Short-term changes caused by fire and mowing in Brazilian Campos grasslands with different long-term fire histories

Questions: What are the main short- term changes in vegetation structure after fire and mowing in Campos grasslands? Are there differences in functional vegetation group responses between sites with diverse fire histories and different treatments (fire andmowing)? Location: Subtropical grasslands in Porto Alegre, Brazil, 30 03' S, 51 07' W. Methods: In two sites with different fire histories: FB - frequently burned grasslands and E - exclusion of fire for 6 yr, seven pairs of plots were examined. In each pair, fire and mowing treatments were established. Bare soil and litter cover were estimated. Vegetation releve ' s were conducted, plants identified, their cover estimated and stems counted (except for graminoids). Later, plants were grouped according to their functional group (graminoids, forbs and shrubs) for statistical analyses. Observations were conducted 30, 90 and 360 d after treatments. Results: Burned plots always showed a higher percentage of bare soil, whilst mowed plots had higher litter cover. Fire enhanced graminoid and forb cover, but did not affect shrubs. Species turnover was very high, mainly in burned plots in site FB and in mowed plots in site E. Species diversity in burned plots was the same in sites FB and E 1 yr after treatments, contrary to our hypothesis. However, in mowed plots, the number of species tended to decrease 1 yr after treatments for both sites FB and E. Conclusions: The most important short- term effect was the removal of litter and consequent opening of gaps, mostly by fire. This stimulated vegetation regeneration and provided microsites for the establishment of new species. However, fire did not enhance plant diversity, as we had hypothesized. Moreover, the disturbance history of sites should be considered, since vegetation in these sites responded differently to fire andmowing.Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq